1. Field of the Invention
The present invention relates to a digital TV (DTV), and more particularly, to a method of transmitting/receiving additional information in a digital TV servicing an electronic program guide(EPG).
2. Discussion of the Related Art
Lately, as broadcasting media such as cable TV broadcasting, digital TV broadcasting and the like are diversified, the number of broadcast channels and programs as well as broadcasting stations increases by geometric progression.
Therefore, it is not easy for audiences to select their favorite programs from a number of broadcast channels and programs.
Digital TV (hereinafter abbreviated DTV) provides a program guide or an electronic program guide(hereinafter abbreviated EPG) for the convenience of the audiences.
EPG is the additional information enabling to help the audiences to watch TV more conveniently, whereby the audiences enable to gain the information about the current and coming broadcast programs on TV screen without other guide media such as newspapers and the like.
Moreover, there is PSIP (program and system information protocol) defining both EPG and SI (system information.
PSIP has been proposed as a standard for ATSC (advanced television systems committee) of the digital broadcasting TV.
PSIP transmits and receives A/V data constructed with MPEG-2 video and AC-3 audio formats, and includes various tables enabling to transmit the information about the channels of the respective broadcasting stations as well as the programs of the respective channels.
And, PSIP can support a main function for providing A/V services of the user demand broadcast as well as an additional function of broadcast guide services such as EPG.
In this case, the channel information for the channel selection and another information such as a packet identification number (PID) for the A/V reception are transmitted through a virtual channel table (VCT), while the information such as EPG of the broadcast programs of the respective channels is transmitted through EIT.
Besides, PSIP further includes STT (system time table) for time information, RRT (rating region table) to transmit information about the regions and consultation organs for the program rates, ETT (extended text table) for additional explanation about the channels and broadcast programs, MGT (master guide table) for the management of versions and PIDs of the respective tables, and the like.
Such tables are transmitted by the data structure called sections.
Each of the tables has a basic unit of section, and the combination of at least one of the sections constructs one table.
Yet, EPG has the limited and simple information about the programs, and particularly, the information constructed mainly with characters only.
Hence, the audience anxious to be informed of the contents of a certain program through TV has no other way but to read the corresponding story provided by EPG.
Yet, the story is the character information only, thereby has a limitation in inducing interests of the audiences.